Systems and methods for selecting and manipulating objects in computer-based modeling environments are known. Examples of existing systems that select and manipulate objects include circuit board design systems and systems used for designing mechanical objects, such as automobiles and airplanes. Some systems typically impose restrictions on a user, such as placing objects such as circuit elements on predefined planes. Other systems require a user to specify a location of a component with high precision in three dimensions and three angular orientations. The devices commonly used for providing information to the modeling system include alphanumeric input devices, such as keyboards, and cursor-based devices operating in two dimensions, such as computer mice and trackballs. Present computer-based modeling systems generally do not permit a user to readily modify an object that has been selected.
The stringent rules that present computer-based modeling systems impose and the inability of users to select, manipulate, and modify objects in a manner more akin to natural motion limits the ability of users to create models of three-dimensional objects.